This proposal is for the development and evaluation of an X-ray diagnostic imaging system based on a CCD type solid state image sensor having 2048x2048 pixels in a 55x55 mm format. The proposed test and evaluation program is designed to demonstrate the substantial superior X-ray imaging performance of this lens coupled CCD image sensor system as compared to X-ray image intensifier/television camera systems. While the superior image quality of a lens coupled system has been recognized for some time, they have not been sensitive enough. The new dimension of this proposal is the large format CCD television camera which allows for moderate demagnification in the optics and has a quantum efficiency exceeding 50% combined with readout noise equivalent to only a few X-rays per picture element. The CCD dynamic range exceeds 104 and the spatial frequency response at the 2048 pixel pitch (18.4 line pairs per mm) is approximately 50%. The proposed CCD based X-ray imaging system is expected to afford substantially higher contrast and other performance improvements as well as potentially lower overall system cost compared to state of the are image tube based systems. Princeton Scientific Instruments has the CCD and electronic equipment in hand to assemble the proposed CCD based X-ray imaging system and the skills to optimize the system performance and analyze the test results.